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Aftermarket pistons?

DenverR1

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I have a 17 850 turbo and one side is down to 105 compression. Apparently BRP pistons are backordered until July. Anyone know where I can get a pair? Or are there any aftermarket brands that I could trust on a turbo sled?
 

DenverR1

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Big shout out to the Crank Shop in Vermont! They had 2 pistons in stock, and also the power valve gaskets that ski-doo had on backorder until September!
 

donbrown

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I talked with piston manufacturers 10 years ago ... They will make a "batch" of pistons for most any application.

Why do you think the side is down to 105 compression ? Too much boost , Too lean , fuel mapping issues? Fuel mixture.

10 minute WOT hilclimbs :eyebrows:
 

DenverR1

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I bought a used turbo 850 with 700 miles, ridden at 6000 elevation, where I'm at 12000. Turns out the fuel pump went bad and my afr was too high on WOT climbs. I hit knock sensor 4 times. After replacing the fuel pump it still has a horrible bottom end bog. We are talking 1 1/2 seconds before the sled hardly moves. Took it to my dealer and had the compression tested and one side is 105. I'm really hoping that takes care of it. I'm worried there is more going on because while 105 is low, I'm not sure it would cause it to bog this badly.
 

donbrown

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I bought a used turbo 850 with 700 miles, ridden at 6000 elevation, where I'm at 12000. Turns out the fuel pump went bad and my afr was too high on WOT climbs. I hit knock sensor 4 times. After replacing the fuel pump it still has a horrible bottom end bog. We are talking 1 1/2 seconds before the sled hardly moves. Took it to my dealer and had the compression tested and one side is 105. I'm really hoping that takes care of it. I'm worried there is more going on because while 105 is low, I'm not sure it would cause it to bog this badly.

I would take a look at the fuel / program and see what is going on.

Maybe adjust it and reflash ?
 

BIG JOHN

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if you lost compression verify your tune/fuel...
new pistons wont fix deto...
RKT has a 2 ring stocker replacement...
 

Teth-Air

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I bought a used turbo 850 with 700 miles, ridden at 6000 elevation, where I'm at 12000. Turns out the fuel pump went bad and my afr was too high on WOT climbs. I hit knock sensor 4 times. After replacing the fuel pump it still has a horrible bottom end bog. We are talking 1 1/2 seconds before the sled hardly moves. Took it to my dealer and had the compression tested and one side is 105. I'm really hoping that takes care of it. I'm worried there is more going on because while 105 is low, I'm not sure it would cause it to bog this badly.

Haha, 105 psi on a Polaris is still fine according to the dealer. Only 120 to start. What is stock compression for the Doo?

BTW I had a sled that bogged like that and it was a broken reed valve. Not unlikely for a turbo.
 

blastco2

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What elevation was the compression tested at? And what was the compression of the other hole?

Sent from my VS995 using Tapatalk
 
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